I admit I don't know what a "Zero-order humanist" is!

But below is as simple as I can make things, and I mean this with the greatest of respect, diagrams really do speak a thousand words, whereas my words are not great, I work a lot with diagrams. I would appreciate if you can let me know if you can grok this:

https://medium.com/@eric-bott/forget-greenhouse-gases-ef857af9b168